In order to make it more difficult for Tarkin to be discovered in the event of an ambush, five Lambda-class shuttles were to take the trip from Eriadu to the Death Star, with Tarkin and Lemelisk riding one with the call signEpsilon 5. The shuttles were escorted by six TIE Fighters, three each from Alpha and Beta squadrons.[4] However, Tarkin deliberately arranged not to travel with a full compliment of guards because he felt it allowed him to move unhindered and avoided drawing attention to the Death Star's location.[5] The shuttles departed from the Eriadu Governor's Palace, with Ackbar piloting the Epsilon 5,[6] and Tarkin and Lemelisk beside him in the passenger seats.[5] As the shuttles approached the Vehemence,[4] three BTL Y-wing starfighters from Red Squadron launched into the system and began their attack, escorted by several X-wings. The starfighters engaged and destroyed the TIEs,[4] while the Y-wings opened fire on the escort shuttles with their laser cannons.[5]

Tarkin ordered Ackbar to take evasive action. Instead, he calmly shut down the shuttle's shields, with the intention of allowing the ship to be destroyed, killing Tarkin and Lemelisk along with himself.[5][6] Red Three identified Epsilon 5 and determined Tarkin was aboard,[4] and the Y-wings fired precision shots that struck the rear of the shuttle and sent it spinning uncontrollably. Ackbar taunted Tarkin and informed him he was going deliberately allow their death out of revenge for all the pain Tarkin had caused him and others of his species.[5] Tarkin and Lemelisk fled to an escape pod, purposely leaving Ackbar to his likely death.[5][6] They launched the pod, which shot away spinning violently into space, and activated a distress signal. The pod was only intended for one occupant, so the two were uncomfortable and suffered minor injuries from the flight, with Lemelisk breaking his nose.[5] Meanwhile, the Y-wings continued firing on Epsilon 5 until it was disabled.[4]

Once the shuttle was disabled, Hasti entered the system from hyperspace and arrives with the commando unit, with two Y-wings from Blue Squadron providing escort. The Vehemence launched nine additional TIE fighters – three each from Alpha, Beta and Gamma squadrons – to engage the Rebel starfighters, and the Red Squadron Y-wings joined Blue Squadron in engaging the TIEs and providing cover for Hasti. The Hasti successfully boarded Epsilon 5, where they discovered Ackbar still alive, but found that Tarkin and Lemelisk had escaped.[4] The two Imperials watched the shuttle get boarded and expressed surprise that they would bother rescuing Ackbar, who Tarkin regarded as a "worthless alien."[5][6]

Before the Rebels could turn their attention to Tarkin's escape pod, AdmiralConan Antonio Motti arrived in the system with his flagship Star Destroyer,[5] which was the Steel Talon at the time,[7] despite Tarkin not having requested his assistance for the escort. The Star Destroyer began firing its turbolasers at the Rebel forces,[5] which prevented them from pursuing and capturing the escape pod.[6] Once Ackbar was safely removed from the Epsilon 5, the Y-wings opened fired on the shuttle again and destroyed it.[5] The Rebels then went into hyperspace and fled the system,[4] leaving Motti's Star Destroyer to rescue Tarkin and Lemelisk.[5]

The rescue of Ackbar and his knowledge of the Death Star overshadowed the Alliance's failure at Eriadu, and he was returned to his people as Admiral of the Mon Calamari fleet. Like many planetary resistance groups, the Mon Calamari were initially cautious with the Alliance to Restore the Republic, but Ackbar provided unofficial support and gave tacit approval of the decision by some Mon Calamari to pledge their starships to Mon Mothma's cause.

Because of the historical importance of Ackbar's rescue and recruitment into the Rebel Alliance, it was made into a simulation for BTL Y-wing starfighters, a simulation that Keyan Farlander briefly took part in.[4]

The liberation of Ackbar was first described in the 1987 first edition of The Star Wars Sourcebook, which established that Ackbar was Grand Moff Tarkin's slave and was rescued when an elite Rebel force attacked Tarkin's shuttle as it embarked to the Death Star. The location where this conflict took place was not identified in that book.[8] The battle itself was first featured in the 1994Collector's CD-ROM edition of the LucasArts computer game Star Wars: X-Wing, which it was the last of six "historical missions" that could be played with the Y-wing star-fighter.[4] This battle was later featured again in the 1995 novel Darksaber by Kevin J. Anderson. In that book, which was set in 12 ABY, Bevel Lemelisk recalled the event through a flashback. It was this book that first established the setting of the Eriadu system,[5] which was later reaffirmed in the books The Essential Guide to Characters (1995),[9] and The Essential Guide to Planets and Moons (1998).[6]